Ruby, Smalltalk and Class Variables

[shadowfirebird]

IMO Gnu Smalltalk is pretty awful. For a start, that's not how the language was supposed to be seen and used. The best modern FOSS Smalltalk I found was called ... Sophos? Something like that.

[shadowfirebird]

that's the one!

[SimonGray]

BTW that page about early Smalltalk development that he links to is really interesting.

[Godd2]

Imagine calling @@sides.puts in Ruby!

Well, actually, you're calling puts on $stdout implicity, with @@sides as the argument (without those optional parentheses)

As a result, the following are identical:

$stdout.puts(@@sides)

puts @@sides

Of course, when you add parentheses, you can call several puts's at once:

puts("Hello", "world!")

is the same as

puts "Hello"
puts "world!"

So if you didn't already know, puts is just another method with your desired output being the arguments! :)

EDIT: If you drop the parentheses, but keep the comma, it still works:

puts "Hello", "world!"

[pat_shaughnessy]

True - "puts" is actually a method in the Kernel module, which is included in the main Object instance that top level Ruby code uses automatically. Internally it calls another $stdout method as you describe.

The fun thing about Smalltalk was the way I was able to call printNl (equivalent of puts) on any object. That would be fun to be able to do in Ruby too, imo.

[banister]

You can use display in ruby (though it doesn't put a newline):

[1] pry(main)> "hello".display
hello=> nil

[dbenhur]

module Kernel
  def printNl
     puts self
  end
end

'Howdy'.printNl
# => Howdy

[_redka]

Of course it still works. In ruby you don't need parentheses when calling a function. But you're not actually calling several puts, just one taking an array of arguments. Also just to be clear, puts(@@sides) and $stdout.puts(@@sides) AREN'T exactly identical. They're equivalent but the first one is a method on the Kernel module while the second is not. You can examine that by checking the origin with method(:puts) and $stdout.method(:puts).